[aprssig] Kenwood TH-D7A(G) Retired
Amir Findling K9CHP
sarlabs at gmail.com
Mon Oct 13 11:11:37 EDT 2008
Well, checking out Shannon's cited source, it looks as if the reports
were from 1992 to 2002 with one single occurrence in 2005. Here is a
quote from that last source
http://nepp.nasa.gov/whisker/reference/tech_papers/2005-dadonna-nuclear-reactor-shutdown.pdf
"The tin whisker is a phenomenon the National Aeronautics and Space
Administration
(NASA) has been tracking since the 1940s."
Shannon, I may be the bearer of bad news, as the Drake TR4 having been
around since the mid-60's, I think it may also potentially suffer from
the same "fate"... :-(
* 73 de K9CHP Amir Findling, Member ARRL, ARRL/ W5YI VE, WAC
* www.K9CHP.net <http://www.k9chp.net>
* Senior K9 Handler
* K9 Certification Tester, NYS Federation of SAR Teams
* 1st Special Response Group (1SRG)
Shanon KA8SPW wrote:
> My fellow hams:
>
> Don't be so fast to replace what works. Another case of a law to
> replace or reduce something before the technology is there to provide
> a solution.
>
> Take a read about growing "tin whiskers" and lead free solder. Big
> problem in RoHS circuits. And it don't take long to show up.
>
> "There is electrical risk posed by the other major component of
> solder, tin. For reasons that remain somewhat obscure, tin used in
> electronic devices can form what are called "tin whiskers
> <http://nepp.nasa.gov/whisker/>," thin filaments of the metal up to
> 10mm long that sprout from surfaces covered in the metal. Although the
> causes of the whiskers are obscure, the consequences aren't: whiskers
> that bridge two conducting areas can cause short circuits, causing
> erratic behavior or ultimately destroying the equipment. NASA
> maintains a list <http://nepp.nasa.gov/whisker/failures/index.htm> of
> various military, orbital, and medical failures that have been
> attributed to tin whiskers. Presumably, many failures in equipment
> that is not significant enough to warrant a post-failure analysis are
> also the product of tin whiskers."
>
>
> Notice how manufacturers are keeping quiet about this problem. In
> some electronics it will take a while and then one day, smoke. Won't
> be any rigs of today working say in 30 years like an old Drake TR4
> does today. I won't be buying anything lead free until the problem
> has been solved for some time.
>
> Your millage may vary.
>
> Shanon KA8SPW
>
>
> Sites from the text above:
>
> "Tin Whiskers" http://nepp.nasa.gov/whisker/
>
> "NASA Maintains a list" http://nepp.nasa.gov/whisker/failures/index.htm
>
> The article bellow has pictures with time taken to grow the whiskers
> in different enviroments.
>
>
> *July 2008* - Tin whiskers on _/*Sn-3.8Ag-0.7Cu-1.0Ce/Er/Y
> */*/S/**/older /*/*J*/*/oints/*_
>
>
>
> *"*
> <http://nepp.nasa.gov/whisker/other_whisker/SAC/2008-Hao-whiskers-SAC-Ce-Er-Y-solder.pdf>*Tin
> Whiskers with Special Morphology **"*
> <http://nepp.nasa.gov/whisker/other_whisker/SAC/index.htm>, H. Hao, Y.
> Shi, Beijing University of Technology, July 2008
>
> http://nepp.nasa.gov/whisker/other_whisker/SAC/index.htm
>
>
>
> Bernard Tyers wrote:
>>
>> On 13 Oct 2008, at 07:29, Arno Verhoeven (PE1ICQ) wrote:
>>
>>>
>>> and believe it or not... China has come up with their own set of RoHS
>>> requirements.
>>>
>>> http://www.chinarohs.com/
>>
>>
>> "It's not Just Another RoHS. It's CHINA RoHS!"
>>
>> This is a joke? Yes? I wonder if they will have a RoHS rating for
>> Bindeez beads..
>>
>> I, for one, am glad that the EU (one of the good things they have
>> done recently) are removing Pb from solder. The one time I had to get
>> myself near a large scale soldering/manufacturing station it wasn't
>> pleasant. And I was there only for a few weeks.
>>
>> Now, if we can make some head way on other poisonous chemicals
>> (mercury, PVCs, flame retardents) it would be even better.
>>
>> regards and 73,
>> bernard/ei8fdb
>> ------------------------------------------------------------------------
>>
>> _______________________________________________
>> aprssig mailing list
>> aprssig at lists.tapr.org
>> https://lists.tapr.org/cgi-bin/mailman/listinfo/aprssig
>>
> ------------------------------------------------------------------------
>
> _______________________________________________
> aprssig mailing list
> aprssig at lists.tapr.org
> https://lists.tapr.org/cgi-bin/mailman/listinfo/aprssig
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.tapr.org/pipermail/aprssig_lists.tapr.org/attachments/20081013/db5ff9ab/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/gif
Size: 60 bytes
Desc: not available
URL: <http://lists.tapr.org/pipermail/aprssig_lists.tapr.org/attachments/20081013/db5ff9ab/attachment.gif>
More information about the aprssig
mailing list